Break-away operator for selfrestoring switch



Aug. 22, 1961 s. E. ANDERSON BREAK-AWAY OPERATOR FOR SELF-RESTORINGSWITCH Filed Sept. 10, 1959 CONTROL C l RQU ITS FaG. 5

23 INVENTOR.

NLEY E. ANDERSON STA ATTORNEYS United States "Patent 2,997,556BREAK-AWAY OPERATOR FOR SELF- RESTORING SWITCH Stanley E. Anderson,Niles, Ill., assignor to Illinois Tool Works, Chicago, 111., acorporation of Illinois Filed Sept. 10, 1959, Ser. No. 839,134 4 Claims.(Cl. 20061.41)

This invention relates to switch-operating structures,-

and more particularly relates to structures for causing both operationand restoration of an electrical switch to occur responsive to eachforward operation of a forwardand-return switch operator.

The principal object is to provide a switch operator on the notedcharacter including parts which, following switch operation, arearranged to break away from each other on a continuation of the forwardmovement, thereby permitting restoration of the operated switch whilethe switch operator remains in forward position. Thereby, the operatedtime of the switch is limited to the interval elapsing between arrivalof the switch operator in its switch-operating position and its arrivalin its breakaway position, and is independent of the dwell-time of theoperator in positions forward of its switch-operating position and isalso independent of the return time of :he operator.

A common form of switch generally comprises a spring :ontact memberarranged to be operated by a switch )perator such as a lever or plunger.A minimum amount )f pressure on the lever causes the spring member to be:hrown into its operated position to close and/or open 1 set of contactsat a required amount of pressure. The :witch remains operated, until theoperating pressure is 'elieved, at which time it returns automaticallyto its moperated condition. Such devices have a wide variety if uses andparticularly have been widely adopted for we in systems wherein a seriesof objects each requires l control operation to be performed. In suchsystems it arrangements each object in turn operates the switch ever tocontrol or energize the circuit whereby the :ontrol operation isperformed. As the control operation must often be kept from extendingover an undue period if time, it is necessary that the switch contactsbe closed lnly momentarily.

In one example, a series of bottles or other objects :arried by aconveyor arrangement or belt each in turn lperates a switch lever tooperate the switch contacts. The contacts in turn control a circuit forenergizing a olenoid, to cause print or other markings to be regsteredon each bottle. As the location of each bottle n the conveyor may varywith respect to switch lever, ontrol of the time with precision duringwhich the lever operated is difficult to achieve. If the switch contactsre closed for an unnecessarily long period of time durug the passage ofa bottle past the switch lever, the olenoid is likewise kept energizedto operate the print laten or stamp to be applied to the bottle for acoresponding period. This results in poor print registration r smudgedprinting.

The present invention eliminates the problem of holdrg the switchcontacts operated for an excess period of me by providing a two partswitch operator or lever av-ing one part pivotally mounted on the otherand held 1 fixed relationship thereto by a predetermined force. he forceis created by the field of a magnet mounted etween the two parts. Whenfirst operated by one of 1e moving objects, the lever functions as oneunit due said force to close the switch contacts. After a suffiientmovement is achieved to close the switch contacts 1e other part of thelever is held stationary. If the ressure on the other part continues andexceeds the redeterrnined force, that part is left freeto pivot orPatented Aug. 22, 1961 travel under pressure of the object moving pastit. With the held part of the lever released from the moving part of thelever, the held part immediately returns to its non-operated positionunder pressure of the spring contact member and the switch contacts arecontrolled accordingly. Thereby, only a momentary closing of the switchcontacts results, which in turn insures that a print platen or stamp isheld only momentarily against the object upon which the print is to beregistered and prevents print smudging. When the object has moved pastthe one part, that part is freely attracted back to its unoperatedposition by the magnetic field.

It is, therefore, an object of this invention to provide a switchoperating structure, which is adapted to enable the switch contacts tobe operated for only a determinable time period.

It is also an object of the present invention to provide a switchoperating structure whose travel is controlled independently of theobject moving it, after it has reached a predetermined position.

It is a feature of this invention to provide a switch operatingstructure comprising two separable portions, one of which is operated bythe other to operate a set of contacts whereaf-ter they separate topermit return of the switch to its unoperated condition.

It is another feature of this invention to provide a; switch operatingstructure having one portion thereof pivotally secured to a switchhousing and the other por-- tion pivotally secured to the first poritionand held in:

a predetermined relationship to said first portion until a;

FIG. 1 of the drawings shows one arrangement of a 7 switch I mounted foruse in a conveyor system;

FIG. 2 is a section of the switch actuator arrangement taken along theline 22 in FIG. 1;

FIG. 3 isa view taken along the line 3-3 of FIG. 2;

FIG. 4 is a top plan view of the switch actuator arrangement; and

FIG. 5 is a diagram of the respective actuator positions.

Referring to FIG. 1, it will be seen that the switch assembly 1 ismounted on a bracket 2 adjacent a conveyor indicated at 6. Bottles 7 orother objects are carried by the conveyor 6 past the switch lever 3. Itwill be understood that instead of the cited example in which print isto be registered on the bottles, that other functions such as variousmachine operations may be desired to be controlled responsive to themovement of particular objects past the switch lever 3.

As seen in FIG. 2, the switch lever 3 is pivotally mounted between sides5 on the lever arm 6 by means of pin 4 and bracket 19. Bracket 19 isprovided with a protrusion 25, whose purpose will be explained. Adheringto the lever arm 6 is a small permanent magnet 8, which is partiallysurrounded by sides 5 of arm 6 to provide an excellent magnetic circuittherefor. Magnet 8 in turn holds lever 3 adjacent arm 6 so that arm 6and lever 3 act as a unit.

Arm 6 is pivotally mounted by means of pin 10 between the brackets 11 onthe switch -12. The elongated portion 13 of arm 6 forming one leg of a Utherewith passes underneath pin 10 and extends above the switch plunger14 for operating it.

The plunger 14, when operated, controls the spring members 15 and 16 inany well known manner to open contacts 17 and close contacts 18. Springmembers 15 and -16 are provided as illustrative of any well knownsnap-action switch arrangement; however, many other types of' switcharrangements may be used with the in,- vention. Contacts 17 and 18 eachcontrol respective circuits in any well known manner, and although twocontacts are shown herein the number may be, varied. The controlledcircuits may, for example, be for energizing a solenoid and/or otherelectrical device, which inturn may control, for example, a pneumaticor. hydraulic valve for controlling the operation of a print platen,roll or stamp, all in any well known manner to perform a correspondingoperation.

When a bottle 7 is traveling past the lever 3, it transmits its movementthrough lever 3, magnet 8, and arm 6; The magnet 8 and. arm 6 follow themovement of lever 3 by pivoting as one unit about pin 10. Portion 13,therefore, also rotates to depress or operate, the plunger 14. Theplunger 14 operates the snap-action switch members 15 and 16 to closecontacts 18 and energize a solenoid, for example, for an alreadydescribed purpose. Shortly. thereafter, protrusion 25 on bracket 19encounters the housing of switch 12.

In FIG; 5, it will be seen that the arm 6 and lever 3 in being operated,travels from the position indicated by line 21 to the position indicatedby line 22. With the snap-action switch 14 operated, and protrusion 25held against the switch housing, further movement of the plunger 16 andlever arm 6 is restrained. Alternatively, the movement may be restrainedby the back pressure of the spring contact members. The bottle, 7, ifstill exerting force on the lever 3, therefore, causes the separation oflever 3 from lever arm 6, on exceeding the attractive force of themagnet 8. The lever 3 then freely pivots about pin 4 under the force ofthe moving bottle 7 to a position such as. shown by line 23 in FIG. 5,after which the bottle 7 loses contact with switch lever 3. Bracket 19also prevents the movement of arm 3 beyond the position indicated byline 23 so that it is held within the magnet field of magnet 8.

In the meantime, the lever arm 6 returns to its unoperated position dueto the force of spring members 15 and 16 exerted on plunger 14, as it isfree from the pressure of the moving bottle. Thus the switch is onlymomentarily operated to control the solenoid accordingly. The momentaryenergization of the solenoid results in only the momentary operation ofthe printing apparatus so that the print is properly registered.

Thereafter, as the bottle 7 continues to travel, it travels pastthelever 3. With the force of the moving bottle removed from lever 3, themagnetic field exerted by magnet8 is suflicient to attract the lever 3and return it to its unoperated position adjacent arm 6 so that theoperation may be repeated for the next bottle or object passing theswitch lever 3.

Thus having described one embodiment of my invention, I am appendinghereto. a series of claims which I believe to incorporate the inventiveconcept.

I claim:

1. For use with a switch having a spring member for controllingcontacts, the improvement comprising. a lever. arm arranged to operatesaid spring member to. con; trol said contacts, a second lever arm,means for retaining the secondv lever arms in predetermined relationshipto said first lever arm whereby an object moving said second leverarmmoves said first lever arm'to operate said. spring member andcontacts whereafter; said second lever arm is released from said firstlever arm to permit said spring member and contacts to be returned totheir unoperated condition while said second lever arm is still operatedby said object, said second lever arm being pivotally mounted on saidfirst leverarm, said first lever arm being pivotally mounted onsaidswitch.

2-. Control means for a switch structure of the type wherein aself-restoring switch is mounted on a support: ing structure which alsosupports a switch-operating member mounted for a reciprocable movementbetween a normal position and a switch-operated position, the=controlmeans comprising a driving lever and a driven lever mounted with thesupporting structure of the switch.

for. a. forward and. a return movement betweennormal and forwardpositions, the driven lever being disposed.

directly behind the driving lever, clutch means interposed means toreengage.

3. Control means according to claim 2, wherein at least one of saidlevers is magnetic, the said clutchcomprising a permanent magnetattached to the other lever and normally engaging said one lever.

4. Control means according to claim 2, wherein the said driven lever ispivotally secured to the said support ing structure of the switch, andthe said driving lever is pivotally secured to the driven lever.

References Cited in the file of this patent- UNITED STATES PATENTS KlugNov. 18, 1947" Zazzara' Nov. 17; 1959'

